If a process goes away while reading its fields, but we already have
that process in the list, we should keep it in case the "highlight dying
processes" mode is active. Not only is that expected in this mode, but
this should also ensure parents are in the list when their children are
(wanted for tree mode consistency).
A process can die between reading the directory listing and opening the
directory FD (if HAVE_OPENAT) or /proc files (otherwise) for reading the
process data. This race would cause LinuxProcessList_recurseProcTree to
remove it from the list immediately, which is unexpected in the
"highlight dying processes" mode and can break the tree structure.
This patch closes this race in the HAVE_OPENAT case by only accessing
the process entry after the directory FD has been opened.
man sscanf(3):
A sequence of white-space characters (space, tab, newline, etc.; see isspace(3)).
This directive matches any amount of white space, including none, in the input.
SELinux contexts can be quite long; adjust the column width dynamically
at each cycle to the longest value.
Also with the recent addition of multiple screens, over-long columns can
be moved into their own screen.
Use PF_KTHREAD flag in /proc/[pid]/stat to detect kernel threads.
This fixed an issue when a process's cmdline is empty, htop think
it is a kernel thread.
Add an explicit else clause so a following else branch for a prior if
condition does not get mixed up.
Also force a trailing semicolon and thereby silence current
-Wextra-semi-stmt warnings.
Improve readability of the hwloc_bitmap_foreach_begin loop macro.
A process, whose executable has been replaced and thus marked by htop,
can be re-executed with the replaced executable, with the same PID, in
two ways: the Linux feature checkpoint/restore or re-execution of PID 1.
The actual check is just a string comparison, like the dropped
condition, leading to (almost) no computation overhead.
Zero all the CPU data, like totalPeriod, after its memory allocation via
realloc(3).
Conditional jump or move depends on uninitialised value(s)
at 0x132A9B: LinuxProcessList_scanCPUTime (LinuxProcessList.c:1928)
by 0x1358C3: ProcessList_goThroughEntries (LinuxProcessList.c:2079)
by 0x12A79A: ProcessList_scan (ProcessList.c:627)
by 0x11CA67: CommandLine_run (CommandLine.c:357)
by 0x4A81E49: (below main) (libc-start.c:314)
Uninitialised value was created by a heap allocation
at 0x48396C5: malloc (in /usr/libexec/valgrind/vgpreload_memcheck-amd64-linux.so)
by 0x12F633: xRealloc (XUtils.c:64)
by 0x12F633: xReallocArray (XUtils.c:78)
by 0x1325A8: LinuxProcessList_updateCPUcount (LinuxProcessList.c:207)
by 0x134E0A: ProcessList_new (LinuxProcessList.c:284)
by 0x11C8D0: CommandLine_run (CommandLine.c:301)
by 0x4A81E49: (below main) (libc-start.c:314)
Update merged command-line when started with "Show custom thread names"
disabled and enabling at runtime.
Also only consider showThreadNames when working on userland threads.
Implements support for arbitrary Performance Co-Pilot
metrics with per-process instance domains to form new
htop columns. The column-to-metric mappings are setup
using configuration files which will be documented via
man pages as part of a follow-up commit.
We provide an initial set of column configurations so
as to provide new capabilities to pcp-htop: including
configs for containers, open fd counts, scheduler run
queue time, tcp/udp bytes/calls sent/recv, delay acct,
virtual machine guests, detailed virtual memory, swap.
Note there is a change to the configuration file path
resolution algorithm introduced for 'dynamic meters'.
First, look in any custom PCP_HTOP_DIR location. Then
iterate, in priority order, users home directory, then
local sysadmins files in /etc/pcp/htop, then readonly
configuration files below /usr/share/pcp/htop. This
final location becomes the preferred place for our own
shipped meter and column files.
The Settings file (htoprc) writing code is updated to
not using the numeric identifier for dynamic columns.
The same strategy used for dynamic meters is used here
where we write Dynamic(name) so the name can be setup
once more at start. Regular (static) columns writing
to htoprc - i.e. numerically indexed - is unchanged.
Adds AGRP (autogroup) and ANI (autogroup nice) columns that
report the information from /proc/PID/autogroup, as well as
handlers for '{' and '}' to change the autogroup nice value.
This is guarded by /proc/sys/kernel/sched_autogroup_enabled
such that sampling and/or changing values wont be attempted
unless the kernel feature is enabled.
Fixes: #720
Currently htop does not support offline CPUs and hot-swapping, e.g. via
echo 0 > /sys/devices/system/cpu/cpu2/online
Split the current single cpuCount variable into activeCPUs and
existingCPUs.
Supersedes: #650
Related: #580
This commit is based on exploratory work by Sohaib Mohamed.
The end goal is two-fold - to support addition of Meters we
build via configuration files for both the PCP platform and
for scripts ( https://github.com/htop-dev/htop/issues/526 )
Here, we focus on generic code and the PCP support. A new
class DynamicMeter is introduced - it uses the special case
'param' field handling that previously was used only by the
CPUMeter, such that every runtime-configured Meter is given
a unique identifier. Unlike with the CPUMeter this is used
internally only. When reading/writing to htoprc instead of
CPU(N) - where N is an integer param (CPU number) - we use
the string name for each meter. For example, if we have a
configuration for a DynamicMeter for some Redis metrics, we
might read and write "Dynamic(redis)". This identifier is
subsequently matched (back) up to the configuration file so
we're able to re-create arbitrary user configurations.
The PCP platform configuration file format is fairly simple.
We expand configs from several directories, including the
users homedir alongside htoprc (below htop/meters/) and also
/etc/pcp/htop/meters. The format will be described via a
new pcp-htop(5) man page, but its basically ini-style and
each Meter has one or more metric expressions associated, as
well as specifications for labels, color and so on via a dot
separated notation for individual metrics within the Meter.
A few initial sample configuration files are provided below
./pcp/meters that give the general idea. The PCP "derived"
metric specification - see pmRegisterDerived(3) - is used
as the syntax for specifying metrics in PCP DynamicMeters.
Reading and parsing /proc/<pid>/maps is quite expensive.
Do not check for deleted libraries if the main binary has been deleted;
in this case the deleted binary takes precedence.
Do not check in threads. The check is void for kernel threads and user-
land threads can just inherit the state from the main process structure.
